China's persistent food and drug safety problem

Chinese authorities are scrambling to defuse public outrage over a safety scandal involving rabies vaccines, just one of a string of food and drug scares to hit the country in recent years.

Despite the country's stunning growth over the past four decades, many consumers in the world's second-largest economy still live in fear of consuming toxic food or dangerous or ineffective medicines.

Following are some of the biggest scandals to emerge over the past decade:

July 2018: The Chinese manufacturer of the blood pressure medication Valsartan, which is widely used in the United States and Europe, launches a global recall after the active ingredient is found to have been tainted by a cancer-causing substance.

March 2016: Authorities detain 130 people over the improper storage and transport of millions of dollars worth of mostly expired vaccines, including shots for polio, rabies, hepatitis B and flu. More than 350 government officials are eventually fired or demoted.

April 2012: Police in the eastern province of Zhejiang detain 22 people for making medicine containing chromium, a toxic raw material produced from scrap leather.

July 2012: High levels of a cancer-causing toxin which comes from mould are detected in infant formula from Ava Dairy. The company's production is halted and its formula recalled.

September 2011: Thirty-two people are arrested over the sale of cooking oil made from discarded oil taken from gutters, which was found to contain carcinogens.

November 2011: Authorities break up a ring that made and sold fake medicines -- some using animal feed. More than 65 million medicine tablets are seized and 114 people arrested.

March 2011: Cancer-causing chemicals -- fed to pigs to produce leaner meat -- are found in live pigs. More than 113 people, including 77 government employees, are eventually jailed in relation to the scandal.

December 2010: Fruit vendors in Shanghai complain of burning skin after touching oranges later found to have been dyed with a toxic orange wax.

December 2010: Six people are detained after wineries in northern Hebei province are found to have added sugar, food colouring and artificial flavouring to create knockoffs of famous wines. Several wineries are shut and bottles pulled from shelves.

September 2008: In China's most explosive recent incident, around 300,000 children fall ill, many with renal failure, and six are killed by milk powder laced with the chemical melamine to give the appearance of higher protein levels. Melamine is usually used to make plastic.

Several top executives with Chinese dairy giant Sanlu receive long prison terms and two get the death sentence. The affair also spurs China to pass a new law on additives, strengthen regulatory coordination on food safety, and restructure the agency in charge of food and drug supervision.

July 2008: Four children die and dozens of others fall ill after receiving damaged vaccines in the northern province of Shanxi, but reports only emerge two years later. Local officials at the time had denied a link between the sick children and the vaccines.

June 2007: Several countries recall Chinese-made toothpaste found to contain a chemical used in automobile antifreeze for vehicles. Also that month, US importers of Chinese toys issue recalls after some are found to be coated with toxic lead paint. Similar products are later banned in several other countries.

March 2007: Pet food in North America and around the world is recalled after animals start dying in large numbers. The problem is eventually traced to wheat and rice derivatives from China that were used as ingredients and to which melamine was added.